1. Field of the Invention
The present invention relates to computer displays, interactive displays, input and output methods for computers, and particularly to interactive projection systems.
2. Description of the Related Art
Computers typically include a display for displaying information, and a keyboard and a mouse to enable a user to interact with the computer based on the displayed information. However, this type of computer is adapted mainly for personal use and is unsatisfactory for group usage.
Recently, interactive projection systems have been developed for projecting images on a table top for meetings, presentations, and the like. One conventional projection system includes a projector disposed underneath a transparent table top. The projector projects images onto the under surface or the table top so that the images are visible to people sitting around the table. Another conventional system has a projector that projects an image onto a mirror that is mounted on the ceiling above the projector. The image is reflected off the mirror back onto the table top where users view the image. A third conventional system includes a transparent table top and a mirror installed on the ceiling above the table top. A projector projects an image through the table top toward the mirror, which reflects the image back onto the table top.
However, these projection systems require special furniture or are difficult to install and transport. For example, the first system requires a special transparent table. The other system requires that a projector and mirror be installed at appropriate positions to project images on the table. The user cannot move the table without having to reinstall the projector and the mirror. The third conventional system Includes all of these problems.
It is an objective of the present invention to provide an interactive projection that has only a minimum of required components, that does not require special installation, and that can be easily moved around.
To achieve the above-described objectives, an interactive projection system according to the present invention for displaying an image on a planar surface includes a base, a projector, a convex mirror, and at least one support. The base is disposed on the planer surface. The projector is housed in the base. The projector has an image projecting portion that projects an image along a projection path away from the projector. The at least one support is connected to the base and supports the convex mirror at a position along the projection path so as to face the image projecting portion of the projector and the planar surface.
With this configuration, the at least one support supports the convex mirror so there is no need to mount the convex mirror onto the ceiling above the system. Because the mirror is convex, the image is reflected onto a broader area of the planar surface than if the mirror were flat. Therefore, a large displayed image can be achieved with a relatively small mirror disposed relatively close to the base. The system can be produced in a more compact size.
It Is desirable to further provide a position indicator, a camera, and a processor to the system. The position indicator is for indicating a position on the planar surface. The camera detects the position indicated by the position indicator. The processor is for determining positional relationship of the position indicated by the position indicator and the displayed image on the planar surface, and controlling the projector to include a cursor in the image at the position indicated by the position indicator. With this configuration, the position indicator can be used as a mouse, in that the cursor is displayed depending on the position indicated by the position indicator.
According to one aspect of the invention, the convex mirror is shaped in a xc2xc wedge of a circle am viewed from the image projecting portion. With this configuration, less support is required compared to the case if the convex mirror were shaped like a full circle. When the convex mirror is shaped in a xc2xc wedge of a circle as viewed from the image projecting portion, then the camera can be mounted on the base or on the convex mirror. When the camera is mounted on the base, its image-pick-up portion faces the convex mirror so that the camera detects the position indicated by the position indicator as reflected from the convex mirror. This configuration is desirable because even less support is required to support the convex mirror. When the camera is mounted on the convex mirror, its image-pick-up portion faces the displayed image on the planar surface so that the camera detects the position indicated by the position indicator by viewing the displayed image. This configuration is desirable because the camera detects the position indicated by the position indicator directly, thereby avoiding possible distortion by the mirror.
The convex mirror can be shaped substantially like a torus with a center hole as viewed from the image projecting portion. This configuration is desirable because the convex mirror reflects the image in a torus shape around the base. In this case, it is desirable to orient the camera so that its image-pick-up portion faces the image projection portion or the projector through the center hole of the convex mirror. The system can be more compact. Also in this case, it is desirable that the projector project a torus shaped image with objects and concentric rings, wherein objects on concentric rings nearer a center portion and perimeter edge of the torus image being displayed larger than objects aligned on concentric rings positioned substantially between the center portion and perimeter edge of the torus image. With this configuration, a great many objects can be displayed by positioning them nearer the center portion and the perimeter edge.
It is desirable that the position indicator include an infrared emitter for emitting infrared light to indicate the position and an infrared lens covering the image-pick-up portion of the camera. In this way, the position indicator can be realized by a simple configuration. Also, the infrared filter filters out light of the projected image, so the camera can detect the position of the position indicator without interference from the light of the projected image.
When plural supports are disposed substantially equidistance from each other external from the convex mirror, the image reflected from the projection path off the convex mirror is blocked to produce shadows in the image displayed on the planar surface. These shadows can be used to enhance functionality of the displayed image. For example, the processor can control the projector to display an opening door in the image when the processor determines that the position indicator is moved from a position on one of the shadows to a position away from the shadow, and control the projector to display objects within the door. With this configuration, the door can serve in the manner of a pop-up menu or tool bar. Also, two adjacent shadows can be used to define a networked area within the displayed image.
According to another aspect of the invention, an infrared emitting unit, at least one infrared sensor, and a processor are further provided. The infrared emitting unit is for emitting infrared light in a plurality of patterns. The at least one infrared sensor is for detecting the infrared light emitted by the infrared light emitting unit. The processor is for determining light pattern of the infrared light detected by the infrared sensor and for performing a process that corresponds to the light pattern. With this configuration, the infrared emitting unit can serve as a mouse for sending commands to the processor.